激光增材制造WCp钛基复合材料界面连接机理及力学性能

颗粒增强金属基复合结构件在航空航天、机械制造以及电子电工等领域有着广泛的应有前景.文中选用激光增材选区熔化技术制备碳化钨(WC)颗粒增强TC4复合材料(WC/TC4)，研究了WC颗粒含量和激光功率对复合材料微观组织和力学性能的影响.结果表明，随着WC颗粒含量的增加，复合材料宏观试样成形能力降低，在WC颗粒含量为(0%～15%)时，WC颗粒分布较为均匀，未见微气孔、裂纹的出现，当颗粒含量为20%时，材料内部出现气孔和裂纹，难以成形；在WC/基体的界面处形成了一层TiC和W₂C界面层，界面结合性能良好；随着复合材料内部颗粒含量和激光功率的增加，材料的断裂强度和断后伸长率降低，断裂机理主要为WC颗粒的脆性断裂和沿WC-W₂C界面的层状撕裂.

Interface connection mechanism and mechanical properties of WCp titanium matrix composites fabricated by laser additive

Particle reinforced metal matrix composite structural parts have a wide range of prospects in aerospace, mechanical manufacturing, electronic and electrical fields. This study fabricated WC-reinforced TC4 matrix composites by laser selective melting technology. The effects of WC particle content and laser power on the microstructure and mechanical properties of the composite were investigated. The results show that: with the increase of WC particle content, the forming ability of composite samples decreases. When WC particle content is (0% ~ 15%), WC particles are evenly distributed, and no micro-pores and cracks are seen. When WC particle content is 20%, pores and cracks appear inside the material, making it difficult to form. At the interface of WC/matrix, an interface layer of TiC and W₂C is formed, and the interface bonding performance is good. With the increase of particle content and laser power in the composites, the fracture strength and elongation osf the composites decrease. The fracture mechanism is mainly the brittle fracture of WC particles and the lamellar tearing along the WC-W₂C interface.